1. Field of the Invention
A method of detecting a touch position, a touch position detecting apparatus for performing the method and a display apparatus having the touch position detecting apparatus are provided. More particularly, a method of detecting a plurality of touch positions among a plurality of touching elements, a touch position detecting apparatus for performing the method and a display apparatus having the touch position detecting apparatus are provided.
2. Description of the Related Art
A touch panel is one type of input device that provides an interface between an information communication apparatus having a display and a user. The user directly contacts the touch panel with a finger or a pen so that the user and the information communication apparatus may exchange information.
Using a touch panel is an interactive and relatively intuitive way to operate a computer, as it is similar to touching a button, so that the touch panel is easily used by all ages. Thus, use of touch panels is broadly applied to, for example, cellular phones, personal digital assistants (PDA), information boards in a bank, a public office, a medical center or a tourist center direction board, etc. Such touch panels typically employ a liquid crystal display (LCD) apparatus or a cathode ray tube (CRT).
Touch panels may be classified via the method for detecting the touch, and include, for example, resistive/pressure sensitive types, capacitive/electrostatic types, and an infrared types, among others.
For example, infrared type touch panels use certain characteristics of light, for instance that it travels straight and is blocked by an obstacle, to detect a touch. Infrared type touch panels include an infrared ray light emitting diode (LED) and a photo transistor that faces the infrared ray LED. The infrared ray LED emits light and the photo transistor receives the light. When a light blocking object such as a finger is disposed on the touch panel, light emitted from the infrared ray LED is blocked by the light blocking object. Then, a cell position at which the light is blocked may be detected based on an amount of light received by a light receiving element, such as the photo transistor.
However, infrared type touch panels may not be capable of distinguishing touches that are made by different touching elements. For example, infrared type touch panels may not be able to distinguish a touch of a finger from a touch of a pen, and as a result the touch position of the pen may not be detected.